U.S. patent number 7,665,418 [Application Number 11/461,221] was granted by the patent office on 2010-02-23 for non color-transferable animal litter.
This patent grant is currently assigned to Church & Dwight Co., Inc.. Invention is credited to Dragomir Mark Bracilovic.
United States Patent |
7,665,418 |
Bracilovic |
February 23, 2010 |
Non color-transferable animal litter
Abstract
A non-color transferable animal litter that employs painted
particles and non-painted water absorbent material. The painted
particles are colorfast once dry. Upon wetting the dried painted
particles do not bleed. The water absorbent material may be a
clumping or non-clumping material.
Inventors: |
Bracilovic; Dragomir Mark
(Princeton, NJ) |
Assignee: |
Church & Dwight Co., Inc.
(Princeton, NJ)
|
Family
ID: |
38984858 |
Appl.
No.: |
11/461,221 |
Filed: |
July 31, 2006 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20080022939 A1 |
Jan 31, 2008 |
|
Current U.S.
Class: |
119/173;
119/171 |
Current CPC
Class: |
A01K
1/0152 (20130101); A01K 1/0155 (20130101); A01K
1/0154 (20130101) |
Current International
Class: |
A01K
1/015 (20060101) |
Field of
Search: |
;119/171,172,173 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Swiatek; Rob
Attorney, Agent or Firm: Frenkel; Stuart D. Shear; Stephen
B.
Claims
What is claimed is:
1. A non-color transferable animal litter comprising (a) painted
particles selected from the group consisting of sodium chloride and
calcium magnesium carbonate, and (b) non-painted water absorbent
material.
2. The litter of claim 1, wherein the painted particles are
particles coated with a polymer latex paint.
3. The litter of claim 2, wherein the amount of paint is about 1
wt. % to 10 wt. % based on the weight of the painted particle.
4. The litter of claim 3, wherein the amount of paint is about 0.1
wt. %-5 wt. % based on the weight of the painted particle.
5. The litter of claim 4, wherein the amount of paint is about 0.5
wt. %-2 wt. % based on the weight of the painted particle.
6. The litter of claim 1, wherein the painted particles are
particles coated with an oil based paint.
7. The litter of claim 1, wherein the painted particles are water
insoluble when dry.
8. The litter of claim 1, wherein the water absorbent material is
non-clumping material.
9. The litter of claim 8, wherein the non-clumping material is
selected from attapulgite, Fuller's earth, calcium bentonite,
palygorskite and sepiolite.
10. The litter of claim 1, wherein the water absorbent material is
a naturally clumping clay.
11. The litter of claim 1, wherein the water absorbent material is
sodium bentonite.
12. The litter of claim 1, wherein the water absorbent material is
non-clumping clay combined with clumping agents.
13. The litter of claim 1, wherein the water absorbent material is
non-clay material combined with clumping agents.
14. The litter of claim 1, wherein the water absorbent material is
organic based litter combined with clumping agents or clumping
clays.
15. The litter of claim 1, wherein the water absorbent material is
non-clay substance treated with clumping agents.
16. The litter of claim 1, further including a fragrance.
17. The litter of claim 1, wherein the amount of painted particles
is about 0.1-20 wt % of the animal litter.
Description
FIELD OF THE INVENTION
The present invention relates to an absorbent composition for
animal dross and its method of use. More particularly, the present
invention relates to a litter that displays colored speckles
without being color transferable.
BACKGROUND OF THE INVENTION
Before the advent of litters, pet owner had relegated pets to
outside the home for lack of an area for taking care of pet
excrement. Litters allow pets to take care of waste functions and
live inside the home. House-broken animals, such as cats, are
trained into the habit of urinating and defecating in a specially
provided litter box. Similarly, untrained and caged animals, such
as guinea pigs, urinate and defecate on the floor of their cage,
often in approximately the same floor area of the cage.
Consequently, pet owners, homeowners, veterinarians and laboratory
personnel have added absorbent materials to the litter box or cage
to collect the urine and feces.
The dross-soiled absorbent must be regularly cleaned to maintain a
hygienic environment and to thwart the emission of objectionable
odors from the presence of the urine and fecal matter in the
litter. Removal of fecal matter from any litter is somewhat easy as
they are generally solid objects that can be physically removed
from the litter. However, physical removal of the feces does not
address the issues of removing liquid dross from the litter nor
does it help reduce or eliminate odors caused by the urine absorbed
into the absorbent. Thus it can be said that the removal of the
liquid dross from the litter is harder to execute.
Though the absorbent material aids in absorbing liquid dross,
removal of the liquid dross and identification of the liquid dross
in the litter is still difficult. Therefore, when the odors caused
by the absorbed urine become intolerable, the homeowner discards
the litter box absorbent material entirely. Consequently, the
litter box absorbent material usually is a relatively inexpensive
solid absorbent material, such that an individual cleaning of the
litter box is not particularly economically burdensome.
The most commonly used litter box absorbent materials are
inexpensive clays, such as calcined clays, that are safe and
non-irritating to the animals, and that absorb relatively
substantial amounts of liquids. Other porous, solid litter box
absorbent materials, that are used alone or in combination, include
straw, sawdust, wood chips, wood shavings, porous polymeric beads,
shredded paper, sand, bark, cloth, ground corn husks, cellulose,
and water-insoluble inorganic salts, such as calcium sulfate. Each
of these absorbent materials has the advantage of low cost. For
each absorbent material, offensive odors are eventually caused by
the absorbed urine, and the entire contents of the litter box,
including soiled absorbent material and unsoiled absorbent
material, will eventually have to be replaced.
Currently clumping clays and other water absorbent material are
used to improve litter compositions. An improved composition for
animal litters uses the clayey soils or comminuted rocks, e.g. the
sodium bentonites, comprising at least one water-swellable clay
mineral in the montmorillonite clay family. These water absorbent
materials not only absorb liquid dross, but they aid in the
identification of used litter from unused litter portions. These
water absorbent materials have the ability to clump and harden
after contact with an aqueous liquid such as urine thus
facilitating the removal of only the soiled portion of the litter
in a litter box or cage during cleaning without the necessity of
removing all the litter. The wetted clump has the ability to group
into a size substantially larger than the individual particles
comprising the litter.
Though these improved compositions have eased the owners' task of
removing soiled litter portions, they are still short of addressing
problems associated with the burial or splitting of the clumped
dross. The buried or split clump, if not timely discovered, will
emit offensive odors within a relatively short period of time. Thus
when the clumped dross is buried or split the homeowner must still
either patiently sift through the litter to remove the used
portions or simply discard the partially soiled litter. As a result
the benefits of having a clumped litter diminishes since the
removal of the clumped dross once again becomes a time-consuming as
well as costly process.
The following prior art references illustrate aspects of the
technology of animal litter preparation, and, in particular,
disclose the use of clays in such litters.
U.S. Pat. No. 4,685,420 issued Aug. 11, 1987 to Stuart, discloses
an animal litter composition comprising a water-absorbing polymer
such as a polyacrylate combined with a porous inert solid substrate
such as clay.
U.S. Pat. No. 5,000,115 issued Mar. 19, 1991 to Hughes, discloses
the use of a water swellable bentonite clay as an absorbent litter
material. The clay absorbs the liquids in animal waste which on
contacting the clay agglomerates it into a stable mass easily
separated from the unwetted and unsoiled portion of the
composition.
U.S. Pat. No. 5,267,532 issued Dec. 7, 1993 to Franklin, et al.,
discloses a pH-indicating material maintained on an inert carrier
that is separate from the cat litter material. The pH-indicating
material has dual indicators that provide one color transition at a
low pH and a different color transition at a high pH so that acidic
or alkaline animal urine problems can be visibly detected upon
contact between the animal urine and the pH-indicating material.
The pH-indicating material is water and urine soluble and easily
transferable.
U.S. Pat. No. 5,371,054 issued Dec. 6, 1994 to Pluta, et al.,
discloses an animal litter composition used to diagnose animal
health problems. The composition comprises at least one uncalcined
clay substrate having a calcium oxide content of less than about 5%
by weight and wherein the clay mineral component of said substrate
has a attapulgite content of at least about 35% by weight, in
combination with at least one chemical pH indicator. All pH
indicators are water soluble and easily transferable.
U.S. Pat. No. 6,619,233 issued Sep. 16, 2003 and U.S. Pat. No.
6,763,783 issued Jul. 20, 2004 both to Mochizuki, disclose a
granulated-type, urine-discharge processing material for animals
that discriminates between before-use and after-use. The material
comprises a water absorbent granular body dyed with water soluble
dyes or a water absorbent granular body containing powder of water
soluble dyes (which will make it color transferable), and a water
absorbent surface layer covering a surface of the water absorbent
granular body. The water absorbent surface layer and the water
absorbent granular body are bonded to each other through a
non-continuous water soluble adhesive layer formed of a plurality
of adhesive non-coated parts and a plurality of adhesive coated
parts which is coated on the surface of the water absorbent
granular body. Discharged animal urine is permeated into the water
absorbent granular body through the water absorbent surface layer
and the non-continuous water soluble adhesive layer, or by
dissolving the adhesive coated parts. Thereby, the water soluble
dyes are eluted into the discharged urine so that the water
absorbent surface layer is dyed through the non-continuous water
soluble adhesive layer. The water absorbent granular body is
chiefly composed of vegetable fiber or vegetable powder and
contains inorganic fillers. The water absorbent granular body
further contains powder of a water absorbent polymer so that the
granular body can have rich water absorbing and retaining
properties. No mention is made to clays in the patent.
Color-indicating litters are the most recent advance in litters,
however, use of these litters are still problematic. Despite the
common problem of tracking the litter in the home, these
color-indicating litters may not only be tracked inside the home,
but can discolor home furnishings such as carpets, couches and the
like, making a small problem even worse. A need exists for a litter
that imparts a color but will not bleed into home furnishings even
if tracked by the pet through the home.
SUMMARY OF THE INVENTION
A non-color transferable animal litter is disclosed that contains
painted particulate material and non-painted water absorbent
material. The absorbent material may be any clumping or
non-clumping material known in the art. Once painted, the particles
are colorfast and do not interfere with the function of the
non-painted water absorbent materials. The painted particles are
colorfast, non-water soluble and impart a speckled appearance to
the litter.
DETAILED DESCRIPTION OF THE INVENTION
The non-color transferable animal litter of the present invention
includes non-painted water absorbent material and painted
particles. The water absorbent component may be clumping or
non-clumping in response to wetness. The water absorbent materials
may be naturally clumping clays, e.g. sodium bentonite,
non-clumping clays combined with clumping agents, non-clay
materials combined with clumping agents, organic based litter
combined with clumping agents or even of a clumping clay, such as
sodium bentonite, mixed with any of the above materials. The
painted particles provide the litter with a speckled appearance.
The painted particles in the litter are colorfast and will not
bleed once dried. In the rare situation where a cat's paws may
transfer a dried, hard, non-sticky, colorfast, colored speckle or
portion thereof onto a carpet, couch or similar surface, it may be
easily removed by vacuuming.
The commonly used water absorbent materials useful in animal litter
are clays. The water-absorbent clayey component of the animal
litters of this invention may be, for example, a clayey soil or
comminuted rock containing at least one water swellable clay
mineral. Such clay mineral may be, for example, a montmorillonoid
or smectite, having a three-layer, sheet structure crystal lattice
with two layers of silicon/oxygen tetrahedrons between which is a
central layer of aluminum and/or magnesium/oxygen dioctahedrons or
trioctahedrons. Part of the silicon in the tetrahedral layers may
be substituted with aluminum and part of the aluminum and/or
magnesium in the central octahedral layer may be substituted with
other elements such as lithium, chromium, zinc, or iron.
Contemplated montmorillonoid clay minerals are montmorillonite and
nontronite containing a dioctahedral central layer, and hectorite,
saponite, and sauconite containing a trioctohedral central
layer.
When the foregoing montmorillonoid clay minerals are contacted with
water or water vapor, the water molecules penetrate between the
layers causing interlayer or intracrystalline swelling and
expansion of the entire lattice. This causes the particles of
clayey component in the animal litter to agglomerate thus
facilitating the removal of only that portion of the litter which
is swelled by urine or other aqueous waste liquid.
The often used clayey component of the animal litter of the present
invention is a comminuted bentonite, more preferably a sodium
bentonite, which contains a preponderant amount of montmorillonite
clay mineral. The use of bentonite clays in a variety of
applications, such as a component in drilling muds, is well known.
Bentonites are economical, readily available clays, with certain
forms capable of hydrating and swelling in the presence of water.
The swelling properties of bentonite are related to the
exchangeable cations present in a particular bentonite ore. The
water-swellable bentonite clays contain various exchangeable
cations, including sodium, potassium, lithium, ammonium, calcium
and magnesium. Although any of these cations can be the predominant
exchangeable cation of the bentonite clay of the present invention,
bentonite clays often include a variety of exchangeable
cations.
The water-swellable bentonite clays useful in the animal dross
absorbent compositions of the present invention include any
water-swellable bentonite clay that hydrate in the presence of
water, erg., swell in the presence of water. The water-soluble
bentonite clay can be selected from the group consisting of sodium
bentonite, potassium bentonite, lithium bentonite, calcium
bentonite and magnesium bentonite; or combination thereof. The
bentonite clay can be any member of the dioctahedral or
trioctahedral smectite group, or a mixture thereof. Examples
include Montmorillonite, Beidellite, Nontronite, Hectorite and
Saponite; or combinations thereof.
The animal litter market is dominated by clays. However, the
naturally clumping clays are not the only sort of water absorbent
material useful in the litter. As mentioned above, other water
absorbent material may be used as litter such as non-clumping clays
which have been converted to clumping clays with the addition of
clumping agents.
These non-clumping clays include Attapulgite, Fuller's earth,
calcium bentonite, palygorskite and sepiolite. The Fuller's earth
clay, also referred to herein as Fuller's earth or clay,
constituent of the compositions of this invention is a natural,
earthy material composed primarily of hydrous aluminum silicates,
while small amounts of non-clay materials can also be present.
Calcium bentonites can range in color from a cream, off-white to a
dark reddish tan color and are frequently referred to in the trade
under designations such as Mississippi Brown and Mississippi White.
These animal litter clays can be divided into heavy weight clays
and light weight clays. Fuller's earth and calcium bentonite are
heavy weight clays. Sepiolite and attapulgite (palygorskite) are
light weight clays.
Other clays useful in the litter may include kaolinite, illite,
halloysite, hormite, vermiculite or mixtures thereof.
With the large part of the animal litter market being dominated by
clumping and non-clumping clays, the remainder of the market is
made up of a variety of non-clay substances. Examples of non-clay
materials that can be used in the present invention and are treated
with clumping agents include zeolites, crushed stone (like
dolomite), light density aggregates and silica gels. Zeolites and
silica gels have been known to be used in the context of odor
maintenance. It should be noted that clumping clays, such as sodium
bentonite, may feasibly be mixed with any of the above materials to
form a water absorbent material.
Still other water absorbent materials may be made of suitable
organic based litter used herein with the addition of clumping
agents. These natural products include, and are not limited to,
such materials as wood based materials such as wood chips, wood
shavings, wood flour, sawdust; straw; clay; porous beads such as
those of polyethylene, polypropylene or polystyrene; paper based
materials such as shredded paper; cloth; alfalfa; cotton; sand;
bark; ground corn husks; ground sugar cane; lignocellulose;
cellulose; calcium silicate; calcium sulfate; various grains (corn,
wheat, flax etc.); or cellulosic products such as sawdust,
woodchips or plant hulls. See e.g., U.S. Pat. Nos. 4,206,718;
4,727,824; 4,883,021; 5,109,804; 5,152,250 which are incorporated
herein by reference.
The clumping agents, or clump enhancing materials, used in
connection with the present invention are those known in the art
such as clumping clays, polysaccharides, water-soluble gums, dry
particulate cellulosic ethers and water-absorbent polymers, among
other things. Clumping agents promote adhesion of the fine size
particles of litter substrates to each other as well as promoting
adhesion of the granules to form an agglomerate when welted.
Preferably, the clumping agent allows the formation of a gelled
agglomerate when exposed to a liquid, such as animal urine.
Natural occurring polymers for use in connection with the present
invention include, for instance, gum arabic, gum karaya, gum
tragacanth, gum ghatti, guar gum, alginates, carrageenan, pectins,
starches, dextran, xanthan gum, gelatin, gluten, corn starch and
dried plants of the Plantago family. An example of a suitable
gum-clumping agent is a water-soluble galactomannan gum, such as a
guar gum or a locust bean gum, or an ether derivative thereof, that
forms a gel upon contact with liquid. Suitable clumping agents of
vinyl polymers include polyvinyl alcohol, polyvinyl esters such
polyvinyl acetate, polyvinylpyrrolidone, polyvinyloxazolidone,
polyvinylmethyloxazolidone, copolymers and mixtures thereof.
Semisynthetic polymers useful as clumping agents in the present
invention include cellulose ethers and guar gum derivatives. The
cellulose ether can be methyl cellulose, hydroxyethyl cellulose,
hydroxypropyl cellulose, ethylhydroxyethyl cellulose,
methylhydroxypropyl cellulose, carboxymethyl cellulose,
hydroxypropylmethylcellulose or mixtures thereof. A combination of
various vinyl, natural and semisynthetic polymers can be used as
clumping agents in the present invention.
Useful polymers are preferably capable of absorbing many times
their own weight of an aqueous fluid such as urine. The formed
agglomerates have sufficient mechanical integrity to be conveyed
from a litter box as a discrete entity using methods typically used
in removing waste product from a litter box such as with implements
or manually by hand.
Other useful clumping agents in the present invention are
commercially available, for example, commercially available
cellulose ethers such as methylcellulose A4M and
hydroxypropylmethylcellulose J15MS, E15LVP, K4M and K15M, are all
available from The Dow Chemical Company. Various starches,
including Starch 1500, are available from Colorcon, a division of
Berwind Pharmaceutical Services, Inc. As another example, guar gum
is available from Aqualon Company.
Although the above discussion is focused on clumping cat litters,
which have a preferred place in the market, as those skilled in the
art will appreciate, the speckles described in the present
invention may also be used with non clumping cat litter.
The paint used in producing the painted particles may include
paints of any kind and any color. Suitable paints include any type
of pigment or dye additive enclosed within a binder vehicle such as
oils, or a typical liquid vehicle such as resins. The pigments and
dyes disposed in the vehicle are preferably non-water soluble when
the paint is dry. One preferred type of paint used is a polymer
aqueous-based latex. The particles that are painted herein include
sodium chloride and calcium magnesium carbonate, such as crushed
dolomite, light density aggregates or any other material of
appropriate particle size.
The paint is applied directly to the surface of the particle via
methods known in the art. The preparation of the painted particles
may be carried out by hand or in any conventional equipment
intended for the blending, spraying, brushing or mixing of the
paint to the particles. Examples of suitable equipment are air
brushers, atomizers, ribbon blenders, V-shell blenders, Marion
mixers, and Norda mixers. A preferred equipment is a ribbon
blender. The mixing time and rate can start from one minute at 30
RPM, Preferably the total mixing time is 1 minute at 30 RPM.
Generally the amount of paint used in the present invention to
obtain desired coverage is about more than 1 wt. % based on the
weight of the particle. In the broadest sense, the paint level can
range from about 0.1 wt. % to 10 wt. %, preferably about 0.1 wt.
%-5 wt. %, and more preferably about 0.5 wt. %-2 wt. % relative to
the particles to which the paint is applied. However, in some cases
higher paint levels may be required to obtain desired coverage on
the particles. To improve the spreading of paint, e.g. latex,
different amounts of water could be used to dilute the paint and
reduce the paint viscosity. The maximum amount of water used to
dilute the paint can vary from 1-50% or more, depending on whether
drying of the painted particles is permissible. Various methods of
drying can be used such as blowing hot or cold air over the coated
particles. At preferred mixing conditions, no separate drying step
is required.
The painted particles are incorporated into the dry litter to give
a speckled appearance. The amount of painted particles in the
litter can be about 0.1-20 wt % or more of the animal litter. The
non-color transferable animal litter may optionally contain a
fragrance component. This may be a powdery "fragrance preblend"
comprising a pleasant smelling oily liquid or "perfume oil"
absorbed on particles of a fragrance carrier having a high surface
to volume ratio. The perfume oil may comprise one or more essential
or synthetic oils which are well-known in the art as providing a
pleasant odor to the composition containing them and also as having
the capability of somewhat masking unpleasant odors. The fragrance
carrier may be any of a group of siliceous and other materials also
well-known in the art as having a high surface to volume ratio and
as being able to absorb perfume oils efficiently while maintaining
their powdery consistency, e.g., dimorphous silicas or
starches.
If a fragrance is utilized, an amount of fragrance in an acceptable
range, typically from 0.1-10%, can be employed. The fragrance could
be added to the painted particle during the course of painting the
particle or after the painted particle is painted and dried. The
litter composition may also optionally contain zinc oxide (ZnO)
which exerts a bactericidal action on the waste products in the
litter. Since at least some of the foul odors of urine and fecal
matter over a period of time is caused by the bacterial breakdown
of the components of such matter, the anti-bacterial action of the
ZnO results in a reduction of the generation of such odors. If
sodium chloride is used as the paint carrier for the colored
speckles, the bactericidal action on waste product is "built
in."
The litter compositions of this invention may be used for a wide
variety of animals and birds, e.g., uncaged household pets such as
cats and dogs, particularly puppies too young to be walked, caged
pets such as hamsters, gerbils and rabbits, caged laboratory
animals such as guinea pigs, mice, rats and monkeys, animals raised
for fur such as mink, barnyard birds such as chickens, ducks and
geese, and pet birds such as parrots, parakeets, canaries and
pigeons. The compositions of this invention are particularly
suitable for use as cat litters.
The invention is furthered by the following examples.
EXAMPLE 1
Several different paints like tempera, acrylic and latex paints
were evaluated to determine the feasibility of sodium chloride
painting and the most economical color with good coverage using a
laboratory two-liter Hobart blender. The paint was poured onto salt
(sodium chloride) at the beginning of the batch. Mild mixing was
sufficient to spread the paint over sodium chloride particles.
Coverage of the sodium chloride particles with paint was uniform.
The speckles were not sticky at the end of the batch and there was
no need to dry the batch. Latex paint was found to be the most
preferable. The minimal latex paint amount for satisfactory
coverage was slightly more than 1%.
EXAMPLE 2
50 lbs. of Benjamin Moore Eggshell Enamel Evening Blue latex paint,
about 1.25 wt. %, were added to 3,950 lb of Morton Medium Solar
Salt in a 5,000 lb ribbon blender. The paint was added by pouring
into a mixer from a 5 gallon pail at both ends of the blender. The
paint dispersed and mixed quickly. Mixing was sufficient to spread
the paint uniformly over the sodium chloride particles. After one
minute the salt was dosed with paint. After ten minutes of mixing
at about 30 rpm, latex/salt speckles were free flowing and had a
uniform blue color. Minimal buildup was noticed on the blender
walls, shaft and ribbon. There was no need to dry the finished
speckles.
EXAMPLE 3
The procedure of Example 2 was carried out except that 75 lbs. of
paint, about 1.88 wt. % was used. The latex/salt speckles produced
were free flowing and had darker blue color in comparison to
Example 2. Again, there was no need to dry the finished
speckles.
COMPARISON OF EXAMPLES 2 AND 3
Examples 2 and 3 were tested on the production line. No problems
were noticed in handling and dosing the batch of latex/salt
speckles. Two super sacks, 2,000 lbs. each Example 2 and 3 were
stored for caking and lumping evaluation. Only very soft lumps were
noticed after a period of five weeks.
* * * * *